Airsporter S barrel question?

[DEAN C.]

I am building a bitsa tap loading Airsporter S model, and I am thinking of shortening the barrel to get the carbine look and make it handle better, or more like my Pro sport anyway. So I am looking for suggestions and advice.

Now I know that short barrels shoot just as accurately as a long one at sub 45 yards, and as my Air arms pro sport shoots superbly to 55 yards with it's very short barrel in comps, so I have no worry about using a short barrel.

The surprising thing to me was that after testing it I have found no choke at all in the original full length S I have!!Is this normal? I might check a few of the other Airsporter actions I have myself to see if the standard models were choked.

How do you all think it will shoot before I chop it??? and has anyone else done it? I have shortened many of my own barrels before for HFT/Ft and hunting air rifles on my lathe so the engineering is no problem.

I would also like to know the barrel length of the original BSA Airsporter carbines/stutzens if anyone can help.

[Geezer]

Should be fine, assuming you crown it properly.

Stutzens had 14" barrels. I think the carbines did too.

[Shed tuner]

yeah, keep it at least 12" and it'll be fine.

[DEAN C.]

Cheers guys, 14" is sounding ok. If anyone can confirm the exact length is as Geezer has said, that's what I will make it to.

I also understand that the carbines/stutzens have a counter bored barrel the same as the later Airsporters, which I have always thought were to help make it easier to fit the front open sight by drilling/tapping through without going into the rifling. I prefer the look of the Mk1/2 Airsporters though where they are just turned, they would be easier to crown as well.



Any other advice welcomed. especially on the latest ideas for smoothing out the A/S internals. Titan spring? Alloy piston/O ring? or has anyone perfected a parachute type lip seal yet?

[Airsporterman]

Hi Dean, as I said, my Carbine deluxe has the counterbored muzzle - I like the look of both but I suppose the through bore would be easier to crown correctly?

I heard or read somewhere that all Airsporter barrels were choked - so that's what I believed.

I have admitted before - I took the hacksaw to my 'plinker' Airsporter Mk4 I had owned since a kid and hacked off about 4 - 5"! I know!
I didn't know much about 'crowning' and the like then. I even replicated the counterbore - don't ask!
To be fair, it was just my plinker rifle and remained a plinker rifle - it wasn't worth much then or now, then I ended up plonking an alloy 'silencer' on the end that probably didn't do much in the way of silencing as the rifle had quite a loud report after fitting it - accuracy - don't even ask - it wasn't that accurate before the 'shortening' - but it looked good and was fun to shoot!

If I can get my Carbine out tomorrow - I will measure the barrel length for you mate!
(time I had a drool over it again!)

ASM

[Airsporterman]

Hi Dean, apologies for not providing sooner!

I hope this info is of some help to you in your project mate!
The usual 'disclaimers' apply - the info is given freely in 'good faith', allowing for my failing eyesight, stupidity, cheap instruments of measurement, poor lighting conditions, shaky hands, nerves etc! (the fact I am half deaf and the other half is stupid can also be a hindrance as it has been throughout my life! )
The information provided is as accurate as I am able and is not supposed to be any way 'representative' or 'conclusive' of any of BSA's products, or indeed of BSA's rifles of the type etc! (especially with regard to the 'Plinker' variant'! )

BSA Airsporter Carbine Deluxe (Boxed) (Walnut stock) .22 cal.
Barrel Length -- 14 ½” inches to the loading tap centre line.
12“ To the breech block shoulder.
Barrel Outside Diameter -- 17 mm approx.
Note: - the rifle has no ‘Counter bore’ at the muzzle end!

BSA Airsporter Centenary Rifle (one of a thousand) .22 cal.

Barrel Length -- 19 5/8” to the loading tap centre line.
17 ½” to the breech block shoulder.
Barrel Outside Diameter – 17mm approx.
Note:- the rifle has a counter bore at the muzzle end!
Counter bore diameter – approx 9.5mm approx internal diameter.
1” along inside barrel.

BSA Airsporter Mk5 (Boxed) Beech Stock. 22 cal.
Barrel Length -- 18 ¾” to the loading tap centre line.
15 ¼” to the breech block shoulder.
Barrel Outside Diameter -- 15.5mm approx.
Note:- the rifle has a counter bore at the muzzle end!
Counter bore diameter – 9.5mm approx internal diameter
1 3/8” approx along inside barrel.

BSA Airsporter Mk1 with Walnut stock (original) .22 cal.
Barrel Length -- 18 7/8” to the loading tap centre line.
18 ½” to the breech block shoulder.
Barrel Outside Diameter -- 15mm at muzzle to 20mm approx at Breech. (note - tapered barrel)
Note:- the rifle has no ‘counter bore’ at the muzzle end!

BSA Airsporter Mk2 with Walnut stock (standard) .22 cal.
Barrel Length -- 18 ¼” to the loading tap centre line.
16 7/16” to the upper part of the sloping edge of the breech shoulder block.
Barrel Outside Diameter -- 15.5mm Approx.
Note:- the rifle has no ‘counter bore at the muzzle end!

BSA Airsporter Mk4 (‘Plinker’) (‘non – standard’ modified ‘carbined’ barrel) .22 cal.
Barrel length -- 15 ½”approx to the loading tap centre line.
12”approx to the breech block shoulder.
Barrel Outside Diameter -- 15.5mm approx.
This rifle has a counter bore – (the sizes are not known as it is fitted with an alloy end piece)

Also:-
Out of Interest, dimensions for a BSA Mercury Barrel not yet fitted to any rifle!

BSA Mercury Barrel .25 cal.
Barrel Length Overall -- 18 ½” from breech end to muzzle end approx.
Barrel Outside Diameter -- 15.5 mm approx.
Note:- the barrel has a ‘counter bore’ at the muzzle end!
Counter bore diameter -- 9.5mm approx internal diameter.
4 3/8” along inside of barrel. (measured twice)
(Another interesting note – the tapping for the foresight fixing passes through the barrel and into the larger muzzle counter bore!)

Hope this helps you buddy!

ASM

[DEAN C.]

Thanks for the replies and especially the information ASM.

If anyone else has any thoughts or advice it would be welcome.

[duomatic410]

Turned an Airsporter barrel down to fit the Rapid, it had lost the first 3inches at the muzzle end to start with.
It's 11.5 inches long and it shoots as good as the Rapid barrel.

[look no hands]

I've just measured my carbine S .22 barrel and it's fourteen and a quarter inches long from muzzle to centre of loading tap with no counter bore, as for your other question that seems to have vanished now, to convert to a parachute seal, you need to use a Diana 28mm seal and either make an adapter up or apparently there is enough meat on a BSA alloy piston head to machine a dovetail on it to except the seal.

Hope that helps.

Pete

[DEAN C.]

Turned an Airsporter barrel down to fit the Rapid, it had lost the first 3inches at the muzzle end to start with.
It's 11.5 inches long and it shoots as good as the Rapid barrel.

Thats interesting John! I haven't checked my other Airsporters but the .22 'S' that I have has no choke. If it's as good as a Rapid it can't be bad, the Rapid barrels are amongst the best barrels made I think, as I have one machined for my Steyr HFt gun and it is very good, especially in the wind.

I've just measured my carbine S .22 barrel and it's fourteen and a quarter inches long from muzzle to centre of loading tap with no counter bore, as for your other question that seems to have vanished now, to convert to a parachute seal, you need to use a Diana 28mm seal and either make an adapter up or apparently there is enough meat on a BSA alloy piston head to machine a dovetail on it to except the seal.

Hope that helps.

Pete

Thanks Peter, that's the length I am going for with a plain end. I think I will round it like the Mk1 Airsporters to protect the crown.
I might also play with a machined head and a Diana seal.Thanks.
The stock I have is an unused very late Airsporter S with the concealed underlever and slightly higher cheekpiece, nice heavy walnut grain as well. I have a new unused push button under lever to go with it so it should look quite nice when completed. I will build it up to make sure it works ok and then get the action blued by Colin Malloy who has done a few other jobs for me including my NJR 100.

Thanks everyone,
Dean.

[greenwayjames]

The information I have is from John Bowkett whose facebook page I edit. He had close ties with the BSA factory going right back. All BSA springers were unchoked. Break barrel rifles used blanks from the rifling machne that had both ends cropped off to remove any choke arising from the manufacturing process. The end that had the bore most concentric with the outer diameter was chosen for the breech end, for looks, and the muzzle counterbored to allow straight through drilling for the sights and to hide the end of the rifling should it be slightly eccentric.
When he worked on what was to become the SuperTen he experimented with barrels and chose one that was made on a large mandrel but retained the choke for best accuracy in a pcp. The springers used a smaller bore in .22" for production reasons.
I asked about the barrel length and he said that he did several conversions on Airsporters where he shortened the barrel to 10" to make ahandy little carbine. His 12ftlbs Mercury/Airsporter conversions used one of his 24 coil spring made for him by Mike Wade. The Fac 18ft/lbs version used a 32 coil spring. These were popular with certain sections of the Northern Ireland airgunning community at the time who preferred shooting British airguns.

[DEAN C.]

Thanks greenwayjames, that is a brilliant insight from JB who I have the utmost respect for, and his guns.


Well if anyone knows what you can do with a BSA barrel it's John bowkett! I'm sure that information will help a lot of people but it also backs up what I had thought after checking a few BSA's I have. Ialso know a couple of world champions are using BSA barrels in German and Austrian guns.
Right it's getting the chop to Carbine length!!

[greenwayjames]

Thanks greenwayjames, that is a brilliant insight from JB who I have the utmost respect for, and his guns.


Well if anyone knows what you can do with a BSA barrel it's John bowkett! I'm sure that information will help a lot of people but it also backs up what I had thought after checking a few BSA's I have. Ialso know a couple of world champions are using BSA barrels in German and Austrian guns.
Right it's getting the chop to Carbine length!!

Glad to be of help. I am in regular contact so if you have an queries. He gaveme a lot of info about the rifling processes they used before hammer forging. Cut rifling was even used on the bottom of the range early Meteors when there were thousands made and regularly shipped all over the world. Pre Gamo. Those were the days.

[Airsporterman]

Thanks for the replies and especially the information ASM.

If anyone else has any thoughts or advice it would be welcome.

You are very welcome mate!
It was a nice excuse to drag them out and measure them!
Did you see the dims for the BSA Mercury .25 barrel? - when you deduct the unusually long counter bore - that's a very short effective bore length and that (I believe) was a production BSA barrel!

I too have a rounded forend stock - do you know if the push button concealed type underlever will fit other Mks?

ASM

[kennp]

The information I have is from John Bowkett whose facebook page I edit. He had close ties with the BSA factory going right back. All BSA springers were unchoked. Break barrel rifles used blanks from the rifling machne that had both ends cropped off to remove any choke arising from the manufacturing process. The end that had the bore most concentric with the outer diameter was chosen for the breech end, for looks, and the muzzle counterbored to allow straight through drilling for the sights and to hide the end of the rifling should it be slightly eccentric.
When he worked on what was to become the SuperTen he experimented with barrels and chose one that was made on a large mandrel but retained the choke for best accuracy in a pcp. The springers used a smaller bore in .22" for production reasons.
I asked about the barrel length and he said that he did several conversions on Airsporters where he shortened the barrel to 10" to make ahandy little carbine. His 12ftlbs Mercury/Airsporter conversions used one of his 24 coil spring made for him by Mike Wade. The Fac 18ft/lbs version used a 32 coil spring. These were popular with certain sections of the Northern Ireland airgunning community at the time who preferred shooting British airguns.

That's very interesting James,
Do you know what John used to do to the piston by way of a seal & piston head?
Are the modern Titan springs the same as those that John used?

Regards,

Pete.